Arylazopyrazole lactone dyes



United States Patent O 3,329,670 ARYLAZGPYRAZLE LACTONE DYES Samuel Dershowitz, Brookline, and Robert B. Woodward, Belmont, Mass., assignors to Polaroid Corporation,

Cambridge, Mass., a corporation of Delaware Filed Feb. 3, 1966, Ser. No. 533,753 7 Claims. (Cl. 260-162) This application is a continuation-in-part of application Ser. No. 444,7'16 filed Apr. 1, 1965 and now abandoned, which in turn is a continuation-in-part of Ser. No. 101,264, tiled Apr. 6, 1961 and now U.S. Patent No. 3,230,085.

This invention relates to photography and, more particularly, to Ian improvement in photographic diffusion transfer reversal processes for obtaining color images.

U.S. Patent No. 2,983,606, issued to Howard G. Rogers, describes and claims the formation of color images by dillsion transfer processes utilizing a reagent which is a dye possessing a silver halide developing function and designated a dye developer. In processes of this type, a photosensitive element containing at least one dye developer and silver halide emulsion is exposed and wetted by a liquid processing composition, for example, my irnmersing, coating, spraying, flowing, etc., in the dark, and the exposed photosensitive element is superposed prior to, during, or after wetting, on a sheetlike support element which may be utilized as an image-receiving element. In a preferred embodiment, the liquid processing composition is applied to the photosensitive element in a substantially uniform layer as the photosensitive element is brought into superposed relationship with the image-receiving layer. The liquid processing composition permeates the emulsion to initiate development. The dye developer is immobilized or precipitated in developed areas as a consequence of the development. This immobilization is apparently primarily due to a change in the solubility characteristics of the dye developer upon oxidation,`

and particularly to a change in its solubility in :alkaline solutions. It may also be due in vpart to a tanning effect on the emulsion by oxidized developing agent and in part` to a localized exhaustion of alkali as a result of development. In undeveloped and partially developed areas of the emulsion, the dye developer is unreacted and diifusible and thus provides an imagewise distribution of unoxidized dye developer dissolved in the liquid processing composition, as a function of the point-to-point degree ofV development of the silver halide emulsion. At least part of this imagewise distribution of unoxidized dye developer is transferred, by imbibition, to a superposed image-receiving layer or element, while the transfer of oxidized dye developer is substantially excluded. The image-receiving layer or element receives a depthwise diffusion of unoxidized dye developer from the developed emulsion without appreciably disturbing the imagewise distribution thereof, to provide the reversed or positive color image of the developed image. The image-receiving element may contain agents adapted to mordant or otherwise fix the diffused, unoxidized dye developer. If the color of the transferred dye developer is affected 4by changes in thev pH of the image-receiving element, this pH may be adjusted in accordance with well-known techniques to provide a pH affording the desired color. The desired positive image is revealed by stripping the image-receiving layer from the photosensitive element at the end of a suitable imbibition period.

The aforementioned diffusion transfer process may be carried out with a single dye developer to obtain a monochromatic color image or two or more dye developers may be employed, as explained below in more detail, in order to obtain multicolored images, as the practitioner may so desire. I

It is desirable, although not essential, when obtaining ice monochrome color images by diffusion transfer processes, that the dye developer be located in the light-sensitive emulsion to which it is to be associated in order to form the desired color image. By placing the dye developer in the light-sensitive emulsion, the necessity of providing an additional layer, and its 'attendant economic disadvantages, is obviated. Moreover, by placing the dye developer in the photographic emulsion, there are obtained the obvious advantages resulting from the fact that the dye developer has less distance to travel in order to reach the silver halide.

Further, where performing a multicolor process, wherein a plurality of photographic emulsions and associated dye developers are employed, by placing the dye developer in the photographic emulsion to which it is to be associated, rather than in `a layer between two photographic emulsions, the chance of undesirable migration of the dye developer to the next adjacent emulsion is avoided.

It has been discovered, however, that certain disadvantages tend to occur when the dye developer is placed in the light-sensitive emulsion in subtractive color processes.

Where a dye developer is complementary in color to the emulsion sensitivity and is situated in such a sensitized emulsion layer, that is, an emulsion layer sensitized to areas of the visible spectrum coinciding with the absorption maximum of the respective associated dye developer, it is obvious that the quantity of actinic energy necessary to accomplish exposure of the sensitized silver halide crystals contained within the emulsion is substantially increased. Due to this absorption by the dye developer of a substantial proportion of the actinic energy available for exposure, there necessarily occurs an undesirable and subst-antial decrease in the relative film speed of the associated photosensitive emulsion.

Moreover, in subtractive color processes employing a multilayer negative, each photosensitive layer theoretically should -be exposable only by approximately one-third of the visible spectrum while transmitting substantially two-thirds of the visible spectrum. For example, the bluesensitive layer has Iassociated therewith a yellow dye developer, and the layer containing the yellow dye developer ideally should absorb only blue light while transmitting green and red. In practice, however, dye developers while often approximating the ideal usually absorb at least some of the light that should be transmitted. It will be apparent from observing the spectral absorption curves of known dyes that they possess tails lapping over into adjacent Wave lengths of the spectrum. The undesirable absorption by such dyes of light that should be transmitted also resuits in slower emulsion speed and reduced color quality.

It has Ibeen discovered that this undesired light -absorption may be substantially reduced or obviated by effecting temporarily, that is, at least for the duration of exposure, a shift of the absorption characteristics of the desired dye developers, so that the undesired absorption by the dye developer is reduced or completely eliminated.

The copending application of Howard G. Rogers, Ser. No 789,080 filed Jan. 26, 1959, and now abandoned,` and the copending application of Elbert M. Idelson and Howard G. Rogers, Ser. No. 418,628 iiled Sept. 3, 1964 as a continuation-in-part of application Ser. No. 788,892 filed Jan. 26, 1959, disclose diffusion transfer processes employing a photosensitive element comprising not less than one silver halide emulsion having associated therewith not less than one image-forming component having a temporarily shifted light absorption spectrum. The photosensitive element may be exposed to a predetermined actinic energy pattern and the exposed silver halide emulsions developed to effect, as a result of development, immobilization of the respective associated image-forming components in the developed areas of the photo- ;ensitive element. An imagewise distribution of mobile .mage-forming components is thus provided in the undeveloped areas of the photosensitive element and may Je, at least in part, transferred by imbibition from the undeveloped areas to a superposed image-receiving layer. A non-reversible restoration of at least a portion of the temporarily shifted image-forming components to their original spectral absorption characteristics is effected, at some stage subsequent to exposure, so as to impart to the image-receiving layer a reversed positive dye image of the latent image exhibiting the desired spectral absorption characteristics.

The aforementioned Idelson et al. application discloses effecting such a temporary shift in the spectral absorption curve by acylating the dye developer. The removal of the acyl groups by hydrolyzing with the alkaline processing composition subsequent to exposure results in a non-reversible shift to a dye developer possessing the desired spectral absorption characteristics.

The present invention relates to another means of effecting the temparary shifting of light-absorption spectrum of the image-forming component. According to the present invention, the desired temporary shift is effected by converting a dye developer having an auxochromic hydroxyl group and a carboxy group in the chromophoric nuclei into the corresponding lactone. Upon contact with the processing solution at some time subsequent to exposure, a non-reversible shift back to the original dye developer occurs.

It is, therefore, an object of this invention to provide novel photographic diffusion transfer processes for obtaining color images and novel products for utilization therein.

Another object is to provide novel photosensitive elements, comprising not less than one silver halide emulsion and not less than one dye developer, possessing increased emulsion speed and improved exposure control.

Yet another object is to provide novel photographic compounds, processes and products for obtaining color images by diffusion transfer processes, wherein the light absorption characteristics of the dye developers utilized to provide said color images are temporarily shifted so that the dye developers absorb actinic energy at wave lengths substantially shorter during exposure than the wave lengths of the respective dye developers ultimately desired.

A further object of the present invention is to provide novel photographic compounds, processes and products for obtaining color images by diffusion transfer processes, wherein the light absorption characteristics of the dye developers utilized to provide said color images are temporarily shifted so that the dye developers absorb actinic energy at wave lengths substantially shorter during exposure than the wave lengths to which the dye developers associated silver halide emulsion is sensitized.

A still further object of the present invention is to provide novel photographic compounds, processes and products for obtaining multi-color transfer images, using integral multilayer photosensitive elements, whereby unwanted absorption, that is, absorption at the wave lengths of emulsion sensitization and absorption reducing exposure of rearwardly positioned emulsions, is avoided.

Still another object is to provide novel photographic processes whereby temporarily shifted dye developers, that is, dye developers the spectral absorption bands of which have been shifted to lower wave lengths prior to exposure of a photosensitive element containing the dye developers, may be restored to their original spectral absorption characteristics subsequent to exposure of the photosensitive element.

A still further object of the present invention is to provide dye developers, the spectral absorption characteristics of which are modified to effect a temporary hypsochromic shift in the wave lengths absorbed during exposure of an associated photosensitive emulsion and 4 which, subsequent to said exposure, may be restored to their original absorption characteristics.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the several steps and the relation and order of one or more of such steps with respect to each of the others, and the product possessing the features, properties and the relation of elements which are exemplified in the following detailed disclosure, `and the scope of the application of which will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection wi-th the accompanying drawing wherein:

FIGURE 1 is a `graphic illustration of the spectral absorption characteristics of a dye developer of the present invention wherein the temporarily shifted absorption curve of the modified ldye developer is superposed upon the absorption curve of the reconstituted, original dye developer.

As indicated previously, the present invention relates to dye developers having temporarily shifted light absorption characteristics so that they absorb actinic en ergy at wave lengths substantially shorter during exposure than the wavelengths of the respective dye developers ultimately desired; and a process for effecting a non-reversible shift back to the original dye developer at some time subsequent to exposure in order to obtain a transfer dye image exhibiting the desired spectral absorption characteristics.

As used herein, the term dye developer denotes a compound containing in the same molecule both the chromophoric system of a dye and also a silver halide developing function, that is, a group or nucleus capable of developing exposed silver halide. The chromophoric system of the dye and the silver halide developing group may be separated by an achromophoric bond, thereby maintaining the color characteristics of the dye unit substantially free from the influence of the developer unit. The term achromophoric bond refers to a bond joining the dye unit -to the developer unit and which does not contribute a color-producing group to the molecule but acts to prevent or interrupt any system of conjugation or resonance extending from the dye unit to the developer unit. Thus, the developer unit is in fact insulated from the dye unit and the color of the dye developer is determined substantially entirely by the chromophoric system of the dye unit. It will be understood that in certain instances, the active substituents responsible for the silver halide developing properties may be generated during photographic utilization, as by alkaline hydrolyiss of an acylated hydroquinone group, e.g., 2,5-bis-trifluoroacetoxy-phenyl, to the free Ihydroquinone.

The expression temporarily shifted dye developer as used throughout the specification and claims denotes a dye developer which has been modified chemically so that its spectral absorption bands have been relocated at substantially shorter wave lengths, that is, a hypsochromic shift of the absorption spectrum, for at least the time interval necessary to accomplish photoexposure of a photosensitive silver halide emulsion associated therewith, the chemically modified dye developer being subject to restoration of the dye developers original absorption characteristics upon simple chemical treatment, such as, for example, hydrolysis.

We have discovered that the aforementioned temporary shift may be effected by converting a dye developer having an auxochromic hydroxyl group, that is, an hydroxyl group in resonance with at least one chromophore in the dye unit, and a carboxy group in the chromophoric system to the corresponding lactone. The term auxochromic hydroxyl group is intended to include enolic hydroxyl groups, as found, for example, in a pyrazolone group. These carboxy and hydroxy groups in the chromophoric system are preferably so separated from one another in a 4 Vor 5 atom linkage, which linkage may be either homogeneous, such as carbon-to-carbon, or heterogeneous, so as to form the corresponding gamma or delta lactone.

From the standpoint of the color of dyes, an auxochrome may best be dened as a substituent atom or group which increases the intensity, (e) of the absorption of light due to a chromophore. An auxochrome may also shift the main absorption band (Amm) to a longer wave length, just as a second chromophore conjugated with the first increases the e in addition to shifting it to a longer Rmx, In an auxochromic system, it is believed tha-t the absorption of light results from the electronic interaction between auxochromes and chromophores by which the contribution of highly conjugated and polarized structures to the resonance of the dye m-olecule is increased.

By converting dye developers having at least one auxochromic hydroxy group to the corresponding lactone there is caused a hypsochromic shift in the spectral absorption characteristics by interrupting the electronic interaction between the respective auxochromes and chromophores.

Accordingly, the temporarily shifted dye developers of this invention may be referred to as dye developers wherein the dye portion of the molecule contains an alkali hydrolyzable lactone group.

The temporarily shifted dye developers may be designated as the lactone formed by condensing a dye developer of one of the following formulae:

XK-Y--OH R and X-X-p 1 Coon wherein:

R may be o-carboxyaryl, such as o-carboxyphenyl, carboxyethyl, carboxypropyl, and substituted derivatives thereof, such as, for example, derivatives wherein one or more hydrogen atoms are replaced by an alkyl substituent, etc.;

Z is a dye radical, preferably an azo dye, wherein said OH substituent is an auxochromic group in resonance with at least one chromophore of said dye radical;

Z1 is a dye radical including a benzene or naphthalene nucleus containing a hydroxy substituent, said COOH being separated from said hydroxy substitutent by 2 or 3 carbon atoms so as to 'be capable upon condensation of forming a gamma or delta lactone;

Y is a chemical bridge joining said X and Y, and preferably an achromophoric insulating bond, and may be a covalent bond or a bivalent organic radical; such as alkylene, preferably a lower alkylene such as Ine-thylene, ethylene, etc.; -CO-; -CH2CONH-; arylene;

X is a developing function such as a hydroquinonyl group.

X may also be any benzene or naphthalene nucleus substituted by at least two substituents selected from hydroxyl, amino and substituted amino groups, provided that at least one of the substituents is in either the ortho or para position with respect to at least one other of the substituents. Such developing functions include, by way of illustration, hydroquinonyl; 3,4-dihydroxyphenyl; 1- hydroxy-4-aminophenyl; 1-hydroXy-4-methylaminophenyl; 1,2,3-trihydroxyphenyl; and 1-hydroxy-Z-aminonaphthyl nuclei. The benzene and naphthalene nuclei may further be substituted by halogenand/or alkyl, substituted alkyl, aryl and substituted aryl groups. In addition, the amino or hydroxy groups may be replaced with radicals which upon hydrolysis by the processing solution will yield hydroxy groups. The replacement of the hydroxy group with such radicals is well known in the art and forms no part of this invention, as such. Examples of such radicals include, by way of illustration, alkoxy, such as methoxy; acetoxy; and haloacetoxy radicals. These radicals may be defined as protected hydroxy groups.

The condensation whereby the lactone is formed is effected between the aforementioned carboxy and hydroxy substituents.

Upon hydrolysis, as b-y contacting the above lactones with the alkaline photographic processing solution at some time subsequent to exposure; a bathochromic shift occurs as the lactones are converted back to their corresponding acids of the above-mentioned general formulae.

A preferred class of temporarily shifted dye developers of this invention are temporarily shifted arylazopyrazolones selected from the group consisting of 4-phenylazopyrazoles and 4-naphthylazopyrazoles wherein the aryl moiety contains a substituent comprising a p-dihydroxyphenyl silver halide developing radical and the pyrazole nucleus contains a substituent of the formula:

@alia wheren the oxygen atom containing the free valence is bonded to the 5 carbon atom of the pyrazole nucleus and the R1 substituent is bonded to the nitrogen atom in the 1 position of the pyrazole nucleus; and R1 comprises a member lof the group consisting of alkyl and phenyl contributing a single carbon atom to complete a gamma lactone nucleus (containing 5 atoms) or two carbon atoms to complete a delta lactone nucleus (containing 6 atoms).

The most preferred group of the aforementioned temporarily shifted arylazopyrazolones may be represented by the following formula:

wherein Xl-NIN- is the diazoniurn radical of a diazotizable aromatic amine of the benzene and naphthalene series, the amine being of the formula: Xl-NHZ; X1 is a benzene or naphthalene nucleus having bonded to a nuclear carbon atom thereof a substituent comprising a silver halide developing function, the substituent preferably'being bonded to a nuclear carbon atom para to the amino group providing the -NIN- moiety; Q may be hydrogen or any of the substituents heretofore substituted in the 3-position of azopyrazolone dyes, e.g., alkyl, preferably an alkyl containing 1-6 carbon atoms, an aryl such as phenyl, an aralkyl such as phenalkyl, carboxanilido, amido, or an N-alkylcarbamyl, preferably one wherein the alkyl moiety contains 1 6 carbon atoms, etc., and R1 has the meaning heretofore noted.

As examples of the aforementioned substitutent comprising a silver halide developing radical, mention may be made of p-dihydroxyphenyl radicals and substituents containing a p-dihydroxyphenyl group bonded to a nuclear carbon atom through -one of the aforementioned divalent organic linking groups, e.g.,

OH (|)H lower alkylene- I OH OH i lower alkylene-C-NH; etc.

The aryl moiety, eg., the ybenzene or naphthalene nucleus of the X1 moiety, may, and in certain of the illustrative examples does contain other substituents, e.g., alkyl or alkoxy radicals bonded to a nuclear carbon atom thereof. The presence or absence of such substituents on the aryl moiety per se comprises no part of this invention, arylazopyrazolones of this nature being heretofore well known in the art.

As examples of aromatic amines for providing the X1-N:N moiety, mention may be made of those disclosed in the U,S. Patents Nos, 3,134,764 and 3,134,765; as well as those disclosed in the application of Elkan R. Blout, Saul G. Cohen, Milton Green and Myron S. Simon, Ser. No. 755,804, led Aug. 18, 1958 and now abandoned; and the copending application of Elkan R. Blout, Saul G. Cohen, Milton Green, Howard G. Rogers, Myron S. Simon and Robert B. Woodward, Ser. No. 401,714, filed Oct. 5, 1964. l

This preferred `class of temporarily shifted dye developers will, upon hydrolysis, form yellow dye developers and are thus particularly useful in association with the blue-sensitive emulsion of a multi-layer photosensitive element.

As examples of species of this preferred class, mention may be made, by way of illustration only, of the following compounds:

(l) OCOCF3 OCOCF3 /\N/ OH l 0:

For purposes of this invention, it is immaterial how one prepares the temporarily shifted lactones of this invention and various synthetic routes may be readily suggested to those in the art in view of the foregoing description.

They may, for example, be prepared by first forming the dye developer containing the designated hydroxyl and carboxyl groups and thereafter converting this dye developer to the corresponding lactone.

A preferred method of forming the dye developer comprises forming the diazonium salt of a protected dihydroxyphenyl derivative of a diazotiza-ble aromatic amine of the formula X1-NH2, i.e., an orthoor parabis-alkoxyphenyl, benzyloxyphenyl or acyloxyphenyl analogue, e.g., p-(2,5diacetoxy--phenethyl)-aniline, and then coupling the resulting diazonium salt with the desired `dye substituent, such as a l-(o-carboxyphenyl)5- pyrazolone.

The protecting groups may be removed prior to photographic utilization to provide the desired dihydroxyphenol developing function. This removal may be effected, for example, by hydrolysis in the presence of alkali. This hydrolysis may be effected prior to conversion to the corresponding lactone, or in lieu thereof, removal of the protective groups and conversion of ythe lactone back to the corresponding acid may be effected at the same time during processing. v

Where found desirable or expedient to do so, the dye developers may Ibe prepared in other ways. Suitable precursors useful in the preparation of 4the dye developers of this invention may be prepared, for example, by processes disclosed in applications referred to in the aforementioned U.S. Patent No. 2,983,606.

It is also immaterial, for purposes of this invention, how one converts the dye developers to the corresponding lactones. Various means of preparing lactones from hydroxy acids broadly would be apparent to the skilled worker. Various enhydrides capable of removing water to form the desired lactone may 4be employed. However, where the compounds to be converted are azo dyes, conversion from the acid to the lactone does not take place as readily, and highly reactive anhydrides such as triuoroacetic anhydride should be employed to effect conversion -to the desired lactone.

The temporarily shifted dye developers of this invention may be employed in both monochromatic and multicolor diffusion-transfer processes, such as those described in the aforementioned copending applications. yIn multicolor processes, it is contemplated that the temporarily shifted dye developers of this invention may be employed in conjunction with the temporarily shifted dye developers disclosed in the aforementioned copending applications Ser. Nos. 418,628, and 789,080, although significant improvements may result from the use of just one temporarily shifted dye developer.

As illustrative of their use in monochromatic diffusion transfer processes, a photosensitive element containing a silver halide emulsion and the desired temporarily shifted dye developer is exposed and then brought into superposed relationship with a suitable image-receiving element. A liquid-processing composition is then spread between the superposed elements, as, for example, by rupturing a frangible container for the processing composition. Containers of this type are described, for example, in U.S. Patents Nos. 2,543,181 and 2,634,886. The processing composition permeates the silver halide emulsion and develops a latent image therein. The temporarily shifted dye developer is also restored, at least in part, to its original spectral absorption characteristics, by hydrolysis upon contact with the processing composition. In unexposed areas, the restored dye `developer will transfer to the superposed image-receiving element to form thereon a positive dye image in terms of exposure, exhibiting the spectral absorption characteristics of the desired restored dye developer.

Monochromatic images may also be obtained by using a lm structure wherein the photosensitive elementis coated over the image-receiving layer and the processing composition must permeate through the emulsion bef-ore reaching the image-receiving layer. A structure of this type 10 is described, for example, in the aforementioned U.S. Patent No. 2,983,606.

Multicolor images may be obtained using dye developers in diffusion transfer processes by several techniques. One process for -obtaining multicolor transfer images by utilizing dye developers employs an integral multilayer photosensitive element such as disclosed and claimed in the copending U.S. application of Edwin H. Land and Howard G. Rogers, Ser. No. 565,135, led Feb. 13, 1956, wherein at least two selectively sensitized photosensitive strata are superposed on a single support and are processed, simultaneously and without separation, with a single common image-receiving layer. A suitable arrangement of this type comprises a support carrying a red-sensitive silver halide emulsion stratum, a green-sensitive silver halide emulsion stratum, and a blue-sensitive silver halide emulsion stratum, the emulsions having associated therewith respectively a cyan dye developer, la magenta dye developer, and va yellow dye developer. The dye developer may be utilized in the silver halide emulsion layer, for example, in the form of particles, or it may be ernpl-oyed asa layer behind the appropriate silver halide emulsion stratum. Each set of silver halide emulsion and associated dye developer strata may be separated from other sets by suitable interlayers, for example, by a layer of gelatin and/ or polyvinyl alcohol.

Multicolor images also may be obtained using the temporarily shifted dye developers of this invention in photosensitive elements comprising at least two sets of selectively sensitized minute photosensitive portions or elements arranged in the form of a photosensitive screen, as disclosed in the aforementioned U.S. Patent No. 2,983,606, and in U.S. Patent No. 2,968,554, issued to Edwin H. Land on Jan. 17, 1961.

A further technique for obtaining multicolor images employs lm structures of the type disclosed in U.S. Patent No. 2,647,049, issued to Edwin H. Land on July 28, 1953.

The liquid-processing composition referred to above comprises at least an aqueous solution of an alkaline compound, for example, diethylamine, sodium hydroxide or sodium carbonate. If the liquid-processing composition is to be applied to the emulsion by being spread thereon, preferably in a relatively thin uniform layer, it may also include a viscosity-increasing compound or film-forming material of the type which, when the composition is spread and dried, forms a relatively firm and relatively stable film. A preferred film-forming material is a high molecular weight polymer such as a polymeric water-soluble ether which is inert to an alkaline solution such as, for example, la hydroxyethyl cellulose or sodium carboxymethyl cellulose. Other iilm-forming materials or thickening agents whose ability to increase viscosity is substantially unaffected if left in solution for a period of time may also be used. Illustrations of suitable liquid-processing compositions may be found in the severa-l patents and copending applications mentioned herein and also in the present application.

It will be noted that the liquid-processing composition may contain an auxiliary or accelerating silver halide developing agent, which developing agent is substantially colorless in at -least its unoxidized form. Examples of preferred accelerating developing agents include 3-pyrazolidones, and preferably 1-phenyl-3-pyrazolidone which is available under the trade name Phenidone, toluhydroquinone, phenyl hydroquinone, 4-methylphenyl hydroquinone, 2,5-bis-ethyleneimino hydroquinone, trimethyl hydroquinone, etc. It is also contemplated to employ a plurality of Vacceleratin-g silver halide developing agents such as a 3-pyrazolidone developing agent and a benzenoidv developing agent, as disclosed and claimed in U.S. Patent No. 3,039,869. Such auxiliary or accelerated developing agents may be employed in theliquid-processing composition or they may be initially incorporated, at least in part, in a stratum of the photosensitive element.

"i i f While a rupturable container, such as shown in FIG- URE 1, provides a convenient means for spreading a liquid-processing composition between layers of a lm unit whereby processing may be carried out within a camera apparatus, the use of such a rupturable container is not necessary to the practice of this invention. In other words, the liquid-processing composition may be applied in other ways. For example, a photosensitive element may be removed after exposure in a suitable apparatus, care being taken to prevent further exposure to actinic light during and after removal, and thereafter permeated with the liquid-processingv composition by coating or otherwise wetting the photosensitive element with the processing composition, after which the permeated, exposed photosensitive element is brought into Contact with the imagereceiving element to obtain the image formation in the manner heretofore described.

The image-receiving element comprises an image-receiving layer of opaque or transparent material which is liquid permeable and dyeable from alkaline solutions and which has been illustrated for purposes of simplicity as comprising a single sheet of permeable material, for example, paper. This element, however, may comprise a support upon which at least one liquid-permeable and dyeable layer is mounted. The support layer may have a water-impermeable subcoat over which the stratum of permeable and dyeable material is applied. In certain instances, the dyeable layer may comprise a layer of liquidprocessing composition which is adapted to remain adhered to the support layer upon stripping.

A preferred material for the image-receiving layer is a nylon such as N-methoxymethyl polyhexamethylene adipamide. Other materials suitable for image-receiving layers comprise a partially hydrolyzed polyvinyl acetate such as that commercially available under the trade name of Vinylite MA-28-l8, polyvinyl alcohol with or Without plasticizers; baryta paper; cellulose acetate with ller, such as, for example, one-half cellulose acetate and one-half oleic acid, gelatin and other materials of a similar nature which are Well known in the art. The image-receiving layer may also contain a mordant, eg., a layer of polyvinyl alcohol or gelatin containing poly-4-vinyl pyridine.

The drawing illustrates the hyposchromic shift induced by converting the preferred dye developers of this invention to the corresponding lactones. The graphic illustration sets forth the spectral absorption curve (solid line) of a temporarily shifted dye developer, l-(o-carboxyphenyl)3carboxanilido 4 [p-( hydroquinonylethyl) phenylazo]-5-hydroxypyrazole lactone (Formula 3), superposed on the spectral absorption curve (broken line) of the hydrolyzed product thereof, 1-(ocarboxyphenyl)3 carboxanilido 4 [p-(-hydroquinonylethyl)phenylazo] S-pyrazolone. It is to be noted that the lactone or temporarily shifted dye developer exhibits a kmax, at 344 mit in methylcellosolve and an analytical density of e=18,000; while the hydroylzed product thereof, i.e., the desired dye developer, exhibits a hmm at 433 my. in methylcellosolve and an analytical density of e=l9,200. This clearly illustrates the optical effects of a temporary modification of a preferred dye developer in accordance with the present invention. It is believed that the slight inflection in the spectral absorption curve (solid line) of the lactone may be due to the presence of a small amount of hydrolyzed material or of uncyclized pyrazolone.

The following examples show by way of illustration and not by Way of limitation the preparation and photographic use of the novel temporarily shifted dye developers of this invention.

EXAMPLE 1 38.4 g. of ethyl benzoyl acetate (0.2 m.) were mixed with 500 ml. of 95% ethanol. This solution was brought to boiling and 37.8 g. (0.2 In.) of o-carboxyphenyl hydral2 zine hydrochloride were added. Following this, a solution of 17 g. (slight excess over 0.2 m.) of sodium acetate in 500 ml. of water was added. The mixture was then heated on a steam bath for 20 minutes, then cooled and 42 g. of a precipitate were collected.

42 g. of this precipitate were warmed With 200 ml. of 10% sodium hydroxide until complete solution took place. The solution was then cooled and carefully acidied with concentrated HCl to obtain 36.6 g. of l-(o-carboxyphenyl)-3-phenyl-5-pyrazolone, having a melting point of l94-6 C.

The diazonium salt prepared from 35 g. of 2,5-bisacetoxy--phenethyl aniline hydrochloride was slowly added, with stirring, to a solution of the aforementioned pyrazolone in 10% aqueous sodium bicarbonate, the solvent being in excess of the amount needed to dissolve the pyrazolone plus that needed for the neutralization of the diazonium solution. The temperature was maintained at 10 to 15 C. After the addition was completed, the mixture was stirred at room temperature for 1/2 hour and then filtered to obtain a wet precipitate.

This Wet precipitate was suspended in l liter of 95 ethanol and treated under nitrogen with 200 ml. of 10% sodium hydroxide on a steam bath for 15 minutes. The solution was then complete. The solution was then cooled and acidied with 50% acetic acid. The resulting mixture was then slowly poured with stirring into 2 liters of water containing 25 ml. of concentrated HCl, and 35.5 g. of precipitate were then collected and washed with water.

This precipitate was 1-(o-carboxyphenyl)-3-phenyl-4- [p hydroquinonylethyl)phenylazo] 5 pyrazolone, having the following structural formula:

HOOG

The above compound is a yellow dye developer, having a melting point of 14S-50 C., and a Amm of 406 ma.

20 g. of the above dye developer were dissolved in 500 ml. of dry acetone. The solution was then added dropwise, with stirring, to a mixture of ml. of dry acetone and 100 ml. of trifluoroacetic anhydride, and the mixture was stirred at room temperature for one hour, and 18.6 g. of precipitate were recovered by filtering, washing with acetone and drying.

This precipitate was l-(o-carboxyphenyl)-3-phenyl-4- [p (2*,5 bistrifluoroacetoxy phenylethyl)phenyl azo]5hydroxy pyrazole lactone (Formula I) having the following structural formula:

The lactone has a kmax. of 351 my. and a melting point of 23S-7 C.

13 EXAMPLE 2 1- (o-caI-boxyphenyl)-3-phenyl-4-[p-(-hydroqu'nonylethyl) phenylazo] -S-hydroxy pyrazole lactone quinonylethyl)phenylazol-S-pyrazolone was prepared inA the manner described in Example 1.

4.0 g. of this compound were dissolved in 125 ml. of dry dioxane. 25 g. of trifluoroacetic anhydride were added and the reaction mixture was then heated ona steam bath for 11/2 hours. It was then poured into 100 ml. of 90% aqueous methanol and heated on a steam bath for another l minutes. The mixture was then shaken with 500 ml. of hexane and the aqueous methanolic layer was separated and poured into water. 1.5 g. of precipitate was then collected by filtration.

The precipitate was 1-(o-carboxyphenyl)-3-phenyl-4- [p hydroquinonylethyl)phenylazo] 5 hydroxy pyrazole lactone (Formula 2), vhaving the following structural formula:

The lactone has a AMX, of 352 me and a melting point of 144-7" C. Y f

EXAMPLE 3 1 o-cmboxy phenyl -3-carboxani lido-4 p- -hydroquinony [ethyl pheny lazo] -5 hyd roxy pylazole lactone 220 ml. of acetic anhydride and 3 ml. of concentrated sulfuric acid were added to 100 g. of tartaric acid. The resulting solution, which took place exothermally, was then heated on a steam b ath for 1.5 minutes. On cooling, 1,2-diacetoxy succinic anhydride, a white crystalline mass, was obtained. This mass was filtered off and washed with benzene.

40 ml. of anhydrous pyridine (dried over KOH pellets) were added with stirring to 20 g. of the 1,2-diacetoxy succinic anhydride prepared above. Immediately after the solution became a greenish-yellow, 12 ml. of glacial acetic acid were added. A precipitate, the pyridinium salt of hydroxy maleic acid, appeared and 50 ml. of anhydrous ether were then added. 10.2 g. of the pyridinium salt, melting point 107 to 108 C., were recovered and washed with 2B ethanol.

20 g. of the pyridinium salt prepared in the above manner were slowly added with stirring to a mixture of 40 ml. of aniline and 50 ml.' of absolute ethanol cooled to 30 C. During the addition of the pyridinium salt, the temperature was maintained so as not to exceed -20 C. When the solution was complete, the mixture was poured into 750 ml. of HC1, cooled to 0 C., and the resulting mixture was then stirred at room temperature for 30 minutes to obtain a precipitate, l-hydroxy maleic acidl-anilide. This precipitate was collected, washed first with dilute HCl, then with water, and dried. In this manner, 20 g. of the anilide were recovered.

20 g. of the anilide prepared above were dissolved in 740 ml. of boiling 95% ethanol. 18.4 g. of ocarboxy phenyl -hydrazine hydrochloride were then added, followed by the addition of 12 g. of sodium acetate dissolved in 500 ml. of water. This mixture was heated on a steam bath for 10 minutes, filtered, and the filtrate was then .poured into 500 ml. of 10% HCl. The resulting precipita-te was collected, washed with water and then dried, yielding 25 g. of oxalacetic acid-1-anilide-2-(o-carboxyphenyl)hydrazone.

25 g. of the hydrazone prepared above land 350 ml. of polyphosphoric acid were heated on a steam bath for 30 minutes. Manual stirring was required to effect solution. The above solution was cooled and then poured into 1 liter of ice water and stirred for 1 hour. The resulting precipitate was collected and washed with water, and 17.5 g. of l-(o-carboxyphenyl)-3-carboxanilido-5-hydroxypyrazole lactone were recovered.

17.5 g. of the above lactone were dissolved in 300 ml. of warm 10% aqueous sodium hydroxide. The solution was filtered, cooled, and the filtrate carefully acidified with concentrated HC1. Upon collecting the precipitate and washing with water, 16.3 g. of l-(o-carboxyphenyl)-3-carboxanilido-S-pyrazolone were recovered.

The diazonium salt from 10.5 g. of 2,5-bis-acetoxy-- phenethyl aniline hydrochloride was coupled into 9.7 g. of the pyrazolone prepared above dissolved in 250` ml. of 10% aqueous sodium bicarbonate. The resulting precipitate was collected as a sludge, triturated with 250 ml. of 10% HC1, refiltered and then Washed with water. The moist filter cake was warmed under a blanket of nitrogen with 1 liter of 95% ethanol. 250 ml. of deaerated 10% aqueous sodium hydroxide were then added and the mixture was warmed on a steam bath for 20 minutes. It was then cooled, neutralized with glacial acetic acid, and poured into 1 liter of 5% aqueous HCl. The precipitate was collected, washed with water and dried to obtain 12.5 g. of a yellow dye developer, 1-(o-carboxyphenyl)3 carboxanilido 4 [p-( hydroxyqunonylethyl)phenylazo]5p yrazolone, having the following structural formula:

HOOG

The dye developer has a melting point of 147 to 149 C., and a max, of 433 mp..

3.0'g. of 'the above dye ydeveloper were partially dissolved in 200 ml. of dry dioxane. This mixture was added dropwise, with stirring, to 30 g. of triuoroacetic acid in 30 ml. of dioxane. After the addition was completed, the mixture was stirred -at room temperature for 30` minutes. 50 ml. of 95 ethanol were. added and the resulting mixture was then poured into an excess of aqueous sodium bicarbonate to obtain 2.8 g. of a precipitate.

This precipitate was l-(o-carboxyphenyl) 3 carboxanilido 4 [p-(-hydroquinonylethyl)phenylazo]-5-hydroxy pyrazole lactone (Formula 3) having the following structural formula:

(INEI -oH.oHl@-N=N H-CONH@ I N /\N/ O OH I The lactone has a Amax, of 344 mp and a melting point of 231-3 C.

The following example illustrates Ithe photographic use of the novel compounds of this invention land is intended to be illustrative only.

l EXAMPLE 4 A 4photographic element was prepared by coating a sub coated cellulose acetate lm base with a tetrahydrofuran solution containing 2% cellulose acetate hydrogen phthalate and 3% of 1-(o-carboxyphenyl)-3-carboxanilido-4-[phydroquinonylethyl)phenylazo] -5 -hydroxy pyrazole lactone. After this layer had dried, `a green-sensitive silver iodobromide emulsion was then applied. The resulting photosensitive element was then exposed, processed by applying an aqueous processing composition comprising:

Percent Sodium hydroxide 3.0 Sodium :carboxymethyl cellulose 5.0 1-phenyl-3-pyrazolidone 1.2 2,5-bis-ethyleneimino hydnoquinone 0.9 S-nitrobenzimidazole 0.12

in a thin layer between the exposed photosensitive element and a superposed image-receiving element prepared by coating a cellulose acetate-coated baryta paper with a solution containing 4% N-methoxymethylpolyhexamethylene adipamide in 80% aqueous isopropanol. After an imbibition period of approximately 2 Iminutes, the image-receiving element was separated from the photosensitive element and contained a yellow positive image of the developed latent image.

Throughout the specification and appended claim, the expression positive image has been used. This expression should not be interpreted in a restrictive sense and is intended to dene the image produced on the imag@ carrying layer `as being reversed, in a positive-negative sense, with respect to the image in the photosensitive element.

The expression superposing or superposed, as used herein, is intended to cover the arrangement of two layers in overlying relation to each other either in face-to-face contact, or separated by at least one layer or stratum of a material which may be a viscous liquid.

In order to illustrate the invention, mention has been made of employing temporarily shifted dye developers which are subjected, at some time subsequent to exposure, to a non-reversible restoration to the ultimately desired spectral absorption characteristics. It should be noted, however, that it is within the scope of the invention to employ a mixture of temporarily shifted dye developers and unshifted dye developers. In other words, where desired, it is within the scope of the invention lto employ a mixture of the lactones described herein and their corresponding acids. At least some beneficial results will occur when only a porti-on of the amount of dye `developer associated with a given emulsion has been subjected to the temporary hypsochromi-c shift. It is also within the scope of the invention to transfer at least some of the temporarily shifted dye developer in its lactone form. Where desired, the lactone so transferred may subsequently be hydrolyed to the acid form, thereby effecting a non-reversible shift in the spectral absorption characteristics of the previously transferred dye developer.

Since certain changes may be made without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. A compound selected from the group Iconsisting of gamma and delta lactones of the formula:

O la Il wherein:

Q is a member of the group consisting of hydrogen, alkyl containing 1-6 carbon atoms, phenyl, carboxanilido and N-alkylcarbamyl wherein the alkyl moiety contains 1-6 carbon atoms;

R1 comprises a member of the group consisting of phenylene and alkylene having no more than two carbon atoms; land X-NIN- is the diazonium radical of a diazotizable aromatic amine of the benzene and nap-hthalene series having bonded to a nuclear carbon atom thereof a substituent comprising a p-dihydroxyphenyl radical.

2. A compound as defined in claim 1 wherein said substituent comprising a p-dihydroxyphenyl radical is selected from the group consisting of:

(?H (|)H -lower alkylene- OH O H an d @uwer aikyieneo Nn- 3. 1 (o-carboxyphenyl)-3-phenyl-4-[p(2',5,bistriflu oroacetoxy ,B phenylethyDphenylazo]-5-hydroxypyrazole lactone.

5. 1- (o-carboxyphenyl) -3-.carboxanilido-4- p- -hydroquinonylethyl) phenylazo -S-hydroxypyrazole lactone.

6. 1-(0carboxyphenyl) 4 [p-(,B-hydroquinonylethyl) phenylazo]-S-hydroxypyrazole lactone.

7, l-(-carboxyphenyl) 4 [p-(-hydroquinonylethyl) phenylazo]5hydroxy pyrazole lactone.

No references cited.

CHARLES B. PARKER, Primary Examiner.

FLOYD D. HIGEL, Assistant Examiner, 

1. A COMPOUND SELECTED FROM THE GROUP CONSISTING OF GAMMA AND DELTA LACTONES OF THE FORMULA: 